Hinged box wrench

ABSTRACT

A sectional box wrench having jaws pivotally hinged to swing apart to permit engagement and disengagement with a fastener is disclosed. Each jaw is provided with a lug half extending in the plane of the jaws which, when the jaws are closed, interlock to form a lug. The interlocking lug construction prevents relative movement between wrench jaws and serves to efficiently transmit torque to the jaws allowing the jaws to be relatively thin. A special socket drive for use with the wrench fits over the lug and has arms that project laterally beyond the lug to engage shoulders formed on the outer side of both jaw halves to transmit torque to the jaws. Adapters to permit the use of conventional ratchet and torque wrenches are shown. Also a special ratchet adapted for use with the hinged wrench and socket combination is also disclosed which permits the drive to be ratcheted while the handle remains substantially in the same position.

United States Patent [191 Kanowsky HINGED BOX WRENCH Benjamin L. Kanowsky, PO. Box 35184, Dallas, Tex. 75235 Filed: Dec. 20, 1971 Appl. No.: 210,056

Inventor:

U.S. Cl. 81/121 R, 81/111 Int. Cl. B25b 13/06 Field of Search 81/121 R, 121 B,

References Cited UNITED STATES PATENTS 11/1961 Cook... J 5/1961 Goldenm.

6/1972 Tyler 81/111 I [57] ABSTRACT A sectional box wrench having jaws pivotally hinged to swing apart to permit engagement and disengagement with a fastener is disclosed. Each jaw is provided with a lug half extending in the plane of the jaws which, when the jaws are closed, interlock to form a lug. The interlocking lug construction prevents relative movement between wrench jaws and serves to efficiently transmit torque to the jaws allowing the jaws to be relatively thin. A special socket drive for use with the wrench fits over the lug and has arms that project laterally beyond the lug to engage shoulders formed on the outer side of both jaw halves to transmit torque to the jaws. Adapters to permit the use of conventional ratchet and torque wrenches are shown. Also a special ratchet adapted for use with the hinged wrench and socket combination is also disclosed which permits the drive to be ratcheted while the handle remains substantially in the same position.

13 Claims, 12 Drawing Figures Patented June 26, 1973 V 3,741,047

2 Sheets-Sheet 1 Patented June 26, 1973 3,741,047

2 Sheets-Sheet 2 BACKGROUND OF THE INVENTION The present invention relates to wrenches and more particularly to a hinged, segmented socket wrench especially adapted for use on nuts or fittings that are not readily accessible with conventional types of socket or other wrenches.

Because of the dictates of design, many mechanical connections are difficult, if not impossible, to reach with conventional wrenches. For example, it is sometimes necessary to turn nuts that are threaded onto long bolts or rods, the ends of which are secured so that the use of conventional closed-end box wrenches is precluded. The existence of an adjacent interfering part of bulk-head may also prevent the use of a conventional open-end wrench. A particular example of this situation may be found in hydraulic systems where, for example, a hydraulic manifold valve assembly will have a series of closely spaced fittings which attach hydraulic lines by nuts coupled to the flared end of the lines. Since the lines are continuous, a socket wrench cannot be placed on the nuts to loosen or tighten them. Similarly, the close proximity of adjacent fittings does not permit the ready insertion of the jaws of a conventional open-end wrench around the nut.

In attempts to provide a wrench that can be used in such restrictive installations, a number of sectional or segmented type wrenches have been developed. The following are representative or typical of this type of wrench as disclosed in the prior art. For example, it is known to pivotally connect matching axially segmented halves of a box type wrench so that the halves can be pivoted apart, slipped about the nut, and pivoted back together in engagement about the nut. Also it is known tosplit conventional sockets into two coacting halves that can be placed about the nut to be loosened or tightened. A special handle with a clamping member at the end engages and secures the socket halves together. Another-solution found in the prior art is to provide a pair of complementary jaws connected for pivotal movement having cooperating lugs which extend perpendicular to the plane of the jaws and are adapted to connect with a wrench handle.

Certain deficiencies are inherent in these and other prior art devices. The former two above-described devices, while providing access to nuts threaded on continuous rods have relatively wide wrench jaws which do not permit accessibility if a closely spaced adjacent abutment exists. Further, engagement of these wrenches about a fitting is sometimes very difficult in hard to reach places. The latter described socket wrench also has-relatively wide jaws in order to transmit sufficient torque without breaking. Further, the arrangement of the lugs, perpendicular to the plane of the jaws, is inefficient and mechanically limits the torque that can be delivered at the nut. Therefore, the attempts to provide a wrench which can be used to engage a nut or fastener on a continuous rod or pipe and, where closely spaced lateral abutments exist, have not been entirely successful. A particular need for a wrench meeting these difficulties arises in hydraulic systems having closely spaced hydraulic fittings. The present invention solves these problems by providing a wrench which expedites mechanical repairs and minimizes cracked knuckles and cursing.

SUMMARY OF THE INVENTION The wrench of the present invention comprises a pair of relatively thin jaws which are pivotally connected to be swung apart and positioned about and closed around a nut. A lug adapted for engagement with a drive socket and handle is formed in two halves, one half each associated with one of the jaw sections. The mating portions of the lug are complementary and interlocking and form a connection which serves to transmit force applied to one half of the lug to the other and to the jaws. A shoulder portion is formed on each jaw half adjacent the associated lug portion. In the preferred embodiment, a special socket adapted to engage the lug is provided having extending members which oppositely engage the shoulders on the jaws to transfer force to the jaws. Adapters are also disclosed which permit the wrench of the present invention to be used with conventional ratchet and torque mechanisms. Also a special ratchet attachment for the wrench is shown which permits a fitting to be rotated by reciprocation of the ratchet handle in a small arc avoiding interference between the handle and adjacent abutments.

The present invention provides a wrench which is of the movable jaw type permitting engagement with threaded fittings located in relatively hard to reach installations. The wrench of the present invention is particularly advantageous in that the depth of the walls of the jaws are relatively thin, thus permitting insertion where conventional or other movable jaw type wrenches could not be used. The portions of the split lug associated with each jaw engage to create a force transmitting connection whereby torque imposed on one portion of the wrench is transmitted to the other, thereby increasing the efficiency of the wrench.

The special socket that is adapted to engage the shoulders provided on the jaws of the wrench also increases the efficiency of the wrench as force is transmitted to the opposite lug to induce a couple about the nut to be engaged. The socket may be used or adapted for use with conventional drive handles of various types.

The above and other objects and advantages of the present invention will become apparent upon consideration of the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a side elevational view of the wrench of the present invention shown in a partially open position in dash lines;

FIG. 2 is a top view of the wrench of FIG. 1;

FIG. 3 is a view similar to FIG. 2 but with one jaw of the wrench shown in an open position;

FIG. 3A shows another form of the hinged connection between the wrench jaws;

FIG. 38 illustrates anotheri embodiment of the wrench of the present invention;

FIG. 4 is a side elevational view, partly in section, illustrating still another embodiment of the present invention;

FIG. 5 is a view of the box wrench of the present invention in engagement with a specially adapted sleeve socket;

FIG. 6 shows the sleeve socket of FIG. 5 along with a special adapter;

FIG. 7 shows another embodiment of the sleeve socket of FIG. 5;

FIG. 8 is a front elevational view of a ratchet usable with the socket and wrench of the present invention;

FIG. 9 is a side elevational view, partly in section, of the ratchet of FIG. 8; and

FIG. 10 illustrates the wrench of the present inven tion positioned on a hydraulic coupling of difficult access.

Referring now more particularly to the drawings wherein like reference numerals are used throughout the several views to designate like or similar parts,

there is shown a hinged box type wrench generally designated by the reference numeral 10. Wrench 10 is comprised of oppositely coacting jaw members 11 and 12 which together form a complete box wrench. .Iaw member 12 includes adjacent members 13 and 14 angularly disposed relative to one another and having interior faces adapted to engage adjacent faces of the fastener. Lug portion member 27 extends from jaw 12. Similarly, jaw portion 11 is comprised of adjacent members 15, 16, 17 and 18 which are angularly disposed relative to one another and which, together with members 13 and 14 of jaw member 12, in the closed position, form a box member to engage the periphery of the fastener. A lug member 26 extends from jaw portion 1 1 and, in the closed position, interlocks, as will be more fully explained, with member 27 to form socket receiving lug 25. Although the box end is shown as being hexagonal, any other configuration could be used. For example, the box end might conceivably be four or eight sided and, of course, could be made in various sizes to accommodate various fittings.

Jaw portions 11 and 12 are connected by a suitable hinged joint so they may be swung or pivoted apart to be engaged about a nut. The hinged connection is best seen in FIGS. 1, 2 and 3 wherein member 14 ofjaw 12 is provided with tongue 40 extending from the lower end terminating in a knuckle portion 38. Adjacent member of jaw 11 is provided with a groove 39 to accept tongue 40 and also terminates on either side of the groove in knuckle members 41 and 42. A pivot pin is received in the interlocking knuckles of the hinge to complete the pivotal connection.

It will be observed that this connection provides a largedegree of freedom of movement and that opposite jaws l1 and 12 may be swung apart 180 or more to accommodate positioning of the nut. Tongue 40 is, of course, angularly oriented with respect to its associated member 14 so that in the closed position it aligns in groove 39 with adjacent member 15.

Other hinged connections between the jaws may also be used to permit the jaw portions to be swung or pivoted apart for engagement about a fitting. For example, FIG. 3A shows a joint having abutting hinge members 43 and 44. Members 43 and 44 are angular with respect to faces 14 and 15, respectively, and each is in the form of a journal. Pin 45 extends through the aligned bore provided in each of the members 43 and 44 and may either be loose or fixed to one of the members. if the joint were of the fixed hinge type, it would permit the jaw halves to be placed adjacent each other around the fitting and be axially moved together with the fixed pin engaging the bore in the other hinge section and the lug halves engaging. The drive wrench would then be affixed to the lug. The construction would be particularly advantageous when a fitting is located between closely spaced abutments which do not permit the wrench jaws to be swung apart sufficiently for engagement about the fitting to be turned. v

To increase the torque transmitted to the wrench jaws, members 13 and 18 of the respective jaw members are each provided with a projecting shoulder 31 and 32, respectively. Shoulders 31 and 32 are adjacent the respective halves 26 and 27 of the lugs. A radius 33 and 34 is provided along the upper surface of sections 18 and 13 from the base of the lug portion to the respective shoulders 32 and 31. The socket especially adapted for use with the wrench of the present invention, which will be described with reference to FIG. 5,

' is provided with oppositely extending projections which engage and are complementary to the projections 32 and 31 so that force applied to the socket is transmitted efiiciently to the jaws of the wrench.

Extending lug member 25 adapted to accommodate the positioning of the wrench thereon may be of any convenient shape such as hexagonal or, as is shown, square. As described above, lug 25 is comprised of complementary mating halves 26 and 27, each associated with jaw portion 11 and 12, respectively. The mating halves 26 and 27 of lug 25 do not abut at a flat surface. In the FIG. 1 embodiment, each lug half 26 and 27 is shown having projecting teeth 28 and 29 of general trapezoidal shape and grooves to complementarily receive the teeth of the opposite lug half. The interlocking connection positively secures the lug halves against relative movement and serves as a force transferring connection to transfer force imposed on one portion of the lug to the other lug and to the jaws of the wrench.

FIG. 4 shows another embodiment of the force transmitting connection between the adjacent lug halves 26 and 27. In this embodiment, designated by the numeral 50, the right hand lug 27 is provided with a detent pin 52 which is adapted to be received into blind bore 51 formed in the opposite mating wall portion of lug 26. This type of interlocking engagement is functionally similar to that shown in FIG. 1 as it serves to minimize relative movement between the opposite halves of the wrench as well as serving to transfer force from one half of the wrench to the other. The remaining construction of the wrench is similarto that described above with hinged jaws 11 and 12 defining fastener engaging faces 13 to 18.

It should be noted that although the specific embodiments of the box wrench shown in FIGS. 1 and 4 have lug projections 25 located at the intersection of two adjacent faces 13 and 18, it is also possible to position the lug at a location intermediate a face member. For example, Iug 25 could be located at the midpoint of member 18 and the bifurcation of the box wrench also at this location along the centerlineof the lug. Similarly, the pivot location of the jaws can also be varied especially when using jaws other than the hexagonal box wrench configuration shown.

It may also be desirable to displace the location of the drive lug axially on the wrench jaws with respect to the fitting to be engaged. FIG. 3B shows an embodiment, designated by the numeral 54, in which jaws 55 and 56, similar to jaws 11 and 12, of the wrench have been axially widened and the lug 57 displaced to one edge of the jaws. This embodiment would accommodate fittings where an interference exists immediately surrounding the fitting, as for example, if the fitting were recessed. The fitting, when fully engaged would extend only a part way into the jaws from the edge opposite the lugs as represented by the dotted line. The socket can then be placed on the lug free of interference from the bulkhead surrounding the fitting. To prevent twisting or damage to the wrench when torque is applied at the lug outboard of the fitting, a special hinged or two-part insert, in the shape of the wrench jaws could'be inserted within the jaws adjacent the end of the fitting, or the hinged wrench may be thicker adjacent lug 57 as indicated by the dotted line 57a to provide additional strength where the shape of the fitting permits. In other respects, the hinged construction of the wrench would be as described above.

A socket especially adapted for use with the present wrench is shown in FIG. 5 and identified generally by the numeral 60. The socket comprises sleeve member 61 which is generally circular in cross-section and is provided with axial recess 63 which conforms in shape to lug projection 25..In the embodiment shown, recess 63 is square in cross-section to be received overlug projection 25 of wrench and is of sufficient depth to fully receive the lug therein. Oppositely extending from the lower end of socket 60 are arms 64 and 65. The configuration of arms 64 and 65 conforms to the curved outer edge members 13 and 18. The terminal ends of the arms abut against shoulders 32 and 31 of the opposite jaws. It will thus be seen that the full depth of lug 25 is received within bore 63 and that projecting arms .64 and 65 of socket 60 extend along opposite members 17 and 18 of the jaw portion 11 and 12 to en- I gage respective shoulders 32 and 31. The upper end of socket 60 is provided with an opening 62 to complementarily receive the end 71 of a conventional wrench drive handle 70. The socket and wrench members of the present invention can be formed of any suitable material, for example, high'quality. tool steel or die cast aluminum treated and hardened.

For some special uses the inner faces of the wrench jaws may be coated with a non-metallic material to further reduce slippage on the fitting and to protect the fitting from damage. The coating material may be a rubber, plastic, polymer or an elastomer. For example, the coating could be a polyolefin, polyurethane, polyvinyl chloride, or teflon.

FIGS. 6 and 7. show various adapters which permit the use of conventional ratchet type and torque wrenches with the wrench of the present invention. Referring to FIG. 6, the socket sleeve 60 of FIG. 5 is shown in connection with an additional adapter 80. For simplicity, the wrench 10'is not shown but would be connected .to the socket 60 as shown in FIG. 5. Adapter 80 is generally square'having projection 83 which is insertable in bore 62 of socket sleeve member 60. A keeper 84 is provided on extension 83 to insure tight engagement between the adapter 80 and socket sleeve 60. Recess 82 provided in one side face 81 of the adapter 80 is generally square and is of a size that conforms to the standard lug extending perpendicularly from torque or ratchet drives. Thus it will be seen that the lug of a conventional ratchet can be inserted in recess 82 of adapter 80 so that the ratchet (not shown) can be rotated to cause sleeve 60 and the box wrench to rotate in the same plane, which is the plane of this page of the drawings, thereby turning the nut.

FIG. 7 shows an alternative form of the adapter shown in FIG. 6. In this embodiment, designated by the numeral 90, a recess 91 adapted to accept the drive projection of a standard ratchet is integrally formed in sleeve 92. Here again, recess 91 conforms in size to the standard extension lug on a ratchet and is provided in sleeve 92 at a position-between projecting legs 64 and 65, and is perpendici til'ai to the longitudinal axis of the sleeve. In other respects, sleeve 92 would be the same as socket 60 shown in FIG. 5 and would accept the lug of a conventional torque or ratchet wrench in recess 91 to drive the box wrench of the present invention. FIGS. 8 and 9 show a modified form of a ratchet type wrench which is particularly adapted for use with the wrench and socket of the present invention. The ratchet is generally designated by the numeral and includes a shank portion at its upper end having recess 104 therein adapted to receive lug 98 of wrench handle 106. Twospaced apart circular flanges 101 and 103 are affixed to the shank. Rotatable between flange members '101 and 103 is gear member 95. Circumferential ridges 96 on the inner side of members 101 and 103 engage complementary grooves in the outer surfaces of gear member 95 to permit gear 95 to rotate between memberslOl and 103. Gear member 95 is provided with internal gear teeth 97, which form the ratchet wheel. Gear teeth 97 are particularly adapted to coact with the two position pawl member 93 which is pivotally mounted at 99 and may be actuated through external lever 94 mounted on the surface of member 101. Thus, pawl 93 may be moved to one-of its two positions through lever 94 and, as is well known in pall and ratchet operation, locking the ratchet to permit rotation in only onedirection. Lug 102 extends from the outer periphery of ratchet wheel 96 and is adapted to be inserted into cooperating bore 62 in socket sleeve 60. I

The above-described ratchet is particularly suitable for use with the wrench and socket of the presentinvention in that it elirninatesthe need for the adapters described and shown in FIGS. 6 and 7. Further, the operation of this ratchet is particularly useful with the present invention because, as will be obvious from FIGS. 8 and 9, gear wheel 95 can be ratcheted to rotate between members 101 and 103 while handle member 106 remains substantially in one position. For example,

in the position of pawl 93 as shown, reciprocating movement of shank 105 through the affixed handle 106 will cause gear 96 to rotate in a clockwise direction displacing lug 102 to the left while handle 106 remains es sentially in the vertical position shown reciprocating through a relatively small arc. i

a This is particularly advantageous when using the wrench in installations similar to that shown in FIG. 10 where access is difficult and bulk heads or abutments are located adjacent either side of the wrench, thus preventing tuming the wrench in conventional manner. FIG. 10 shows the wrench of the present invention 'in a position of use and further illustrates the advantages of the wrench of the present invention. Numerals and 121 represent conventional hydraulic control valves, assembled together to form a manifold or stack valve. Typically, these valves serve many purposes and, for example, would control the'operation of the boom and bucket of a conventional backhoe. As is often the case, the valve bodies are mounted adjacent a bulk head or plate 109. Hydraulic couplings 122 through 126 secure hydraulic hoses to the valve bodies 120 and 121 to provide for the flow of pressure and return fluid to and from the valves. It will be obvious that if itis desired to loosen or tighten coupling 125, access is very limited. The lateral clearance space between coupling 125 and adjacent couplings 123 and 126 is relatively small, thus precluding insertion of a conventional openend or similar wrench. Since hydraulic hoses extend from the couplings 122 through 126, use of a conventional closed-end box wrench is also not possible since the hoses would obstruct engagement of the wrench on the fitting.

The hinged box wrench of the present invention is especially adaptable to use in this installation. The jaw members 11 and 12 are relatively thin so that the wrench may be engaged about the fitting without interfering with the adjacent fittings and without the difficult and time consuming task of removing other fittings and lines to gain access to the fitting to be turned. in use, the wrench member 10 is slipped about the fittings by swinging open jaws l1 and 12 sufficiently apart to permit them to be slipped about the fitting and then closed. With the wrench in place, the interior hexagonal surfaces of the jaws grip the periphery of the nut firmly. Socket member 60 is then slipped into place over lug 25 so that projecting fingers 64 and 65 engage the respective shoulders 31 and 32 in the jaw members 11 and 12'. Conventional drive handle 70 is then inserted into engagement with sleeve 60 at bore 62. After the wrench is thus placed in a working position as described, force applied to the handle of drive 70 will be transmitted to the fitting 125 to loosen or tighten it as desired.

- The design of the present wrench 10 insures that maximum torque is delivered to the fitting and that a minimum of slippage occurs between the jaw and lug halves. For'example, if a force is applied in the direction of the arrow as shown in FIG. 10, imparting a counterclockwise motion to the fitting, force will be transmitted along handle 70, through socket 60 to section 27 of lug 25 and to members 13 and 14 ofjaw l2. Torque will also be transmitted from socket 60 through leg 64 to shoulder32 of jaw 11 and to jaw members 16 and 17 to complete a couple about the fitting. Since the halves 26 and 27 of lug 25 are in interlocking saw tooth engagement, longitudinal'slipping between them is prevented so that maximum torque is transmitted to the nut. Embodiment 50 of the box wrench would operate in a similar manner.

Thus it will be seen that the present invention provides a thin jawed hinged wrench which is especially adaptable for use in tight installations. The wrench, while highly useful in servicing hydraulic equipment, has almost unlimited application. It is highly useful in working on all piping and tubing connections where difficult access is provided either because of adjacent abutments or fittings or continuously running lines. Also the wrench provides a positive grip, minimizing slippage relative to the fitting, thus preventing scarring or damage to the fitting. This advantage has particular application in critical structures such as airframes.

in summary, the present invention provides a wrench with jaws which engage each other to minimize relative slipping and to transmit maximum torque to both halves of the wrench, thereby further allowing the jaw portions to be of relatively thin cross-section. The specially designed socket engaging shoulders provided on the aw portions also further insures maximum transmission of torque to the fitting to which the wrench is applied. Adapters, as described above, permit the use of conventional torque or ratchet wrenches with the wrench of the present invention. A special form of ratchet wrench is shown which may be used with the wrench and socket of the present invention without the necessity of special adapters. It is believed that it will be apparent from the above description and disclosure that the invention comprehends a novel construction of hinged or segmented wrenches and that it is to be understood that other arrangements, modificationsand changes will occur to others skilled in the art and such are to be considered within the spirit and scope of the appended claims.

I claim:

1. A wrench comprising:

at least a pair of jaw members pivotally connected and adapted to be moved to an open and to a closed position, said jaw members having inner faces which are adapted to engage the periphery of a fastener in said closed position,

a pair of lug sections, each of said sections associated with separate adjacent jaw members and coacting at abutting surfaces in said closed position to form a lug, said lug adapted to receive a cooperative wrench socket member to secure the jaws insaid closed position, and

means defining a force transmitting connection between said lug members whereby torque applied by said wrench socket member is transmitted to said jaw members. i

2. The wrench of claim 1 wherein said lug sections extend from said jaw members in the plane of the jaws.

3. The wrench of claim 2 wherein said means defining a force transmitting connection comprise a projection on one of said lug section abutting surfaces and a complementary groove adapted to receive said projection in the other of said abutting surfaces.

4. The wrench of claim 3 wherein said projection is in the form of a tooth and is received in a complementary groovein the abutting lug section. a

5. The wrench of claim 3 wherein said projection is a pin and said complementary groove is a bore.

6. The wrench of claim 1 further including a shoulder on each jaw member adjacent the base of the associated lug section, said shoulder adapted to engage a wrench socket member.

7. A wrench comprising:

a pair of complementary jaw members pivotally connected and adapted for movement to an open and closed position, said jaw members having inner faces adapted to engage the periphery of a fastener in the closed position,

a pair of lug member halves projecting from adjacent jaw members and abutting in a closed position there together forming a lug member, the abutting surfaces interlocking to define a force transmitting connection,

shoulder means on each of the jaw members adjacent the associated lug,

socket means including a body portion having a socket in one end adapted to receive said lug memhers and secure said halves together, and means oppositely projecting from said body adapted to engage said shoulders, and

drive means adapted to cooperate with said socket to transmit torque to said wrench.

8. The wrench of claim 7 wherein said drive means is a ratchet type wrench.

9. The wrench of claim 8 wherein said drive is a torque type wrench.

10. The wrench of claim 8 wherein said ratchet wrench comprises a handle, ratchet means including gear means rotatable in said handle and pawl means engaging said gear, a lug extending from said gear in the plane'of the handle whereby the wrenchinayv be ratcheted with said handle remaining substantially in the same position.

11. The wrench of claim 7 wherein said inner faces of said jaws are coated with a non-metallic protective .is provided with strengthening means I I t l 

1. A wrench comprising: at least a pair of jaw members pivotally connected and adapted to be moved to an open and to a closed position, said jaw members having inner faces which are adapted to engage the periphery of a fastener in said closed position, a pair of lug sections, each of said sections associated with separate adjacent jaw members and coacting at abutting surfaces in said closed position to form a lug, said lug adapted to receive a cooperative wrench socket member to secure the jaws in said closed position, and means defining a force transmitting connection between said lug members whereby torque applied by said wrench socket member is transmitted to said jaw members.
 2. The wrench of claim 1 wherein said lug sections extend from said jaw members in the plane of the jaws.
 3. The wrench of claim 2 wherein said means defining a force transmitting connection comprise a projection on one of said lug section abutting surfaces and a complementary groove adapted to receive said projection in the other of said abutting surfaces.
 4. The wrench of claim 3 wherein said projection is in the form of a tooth and is received in a complementary groove in the abutting lug section.
 5. The wrench of claim 3 wherein said projection is a pin and said complementary groove is a bore.
 6. The wrench of claim 1 further including a shoulder on each jaw member adjacent the base of the associated lug section, said shoulder adapted to engage a wrench socket member.
 7. A wrench comprising: a pair of complementary jaw members pivotally connected and adapted for movement to an open and closed position, said jaw members having inner faces adapted to engage the periphery of a fastener in the closed position, a pair of lug member halves projecting from adjacent jaw members and abutting in a closed position there together forming a lug member, the abutting surfaces interlocking to define a force transmitting connection, shoulder means on each of the jaw members Adjacent the associated lug, socket means including a body portion having a socket in one end adapted to receive said lug members and secure said halves together, and means oppositely projecting from said body adapted to engage said shoulders, and drive means adapted to cooperate with said socket to transmit torque to said wrench.
 8. The wrench of claim 7 wherein said drive means is a ratchet type wrench.
 9. The wrench of claim 8 wherein said drive is a torque type wrench.
 10. The wrench of claim 8 wherein said ratchet wrench comprises a handle, ratchet means including gear means rotatable in said handle and pawl means engaging said gear, a lug extending from said gear in the plane of the handle whereby the wrench may be ratcheted with said handle remaining substantially in the same position.
 11. The wrench of claim 7 wherein said inner faces of said jaws are coated with a non-metallic protective material.
 12. The wrench of claim 7 wherein said jaws are axially wider than the fastener to be engaged whereby the fastener extends axially only part way into said jaws and said lug members are axially displaced toward one edge of the jaws.
 13. The wrench of claim 12 wherein the unengaged portion of the jaws located subjacent the displaced lug is provided with strengthening means. 